Particle beam therapy system and control system for particle beam therapy

ABSTRACT

A particle beam therapy system comprises a charged particle beam generator for generating a charged particle beam, two or more treatment rooms provided with respective irradiation devices for irradiating the charged particle beam, a beam line for transporting the charged particle beam extracted from the charged particle beam generator to the irradiation device in selected one of the two or more treatment rooms, a beam detection processing/control unit for monitoring a beam state of the charged particle beam in one of the two or more irradiation devices, and a selector for switchably selecting one of the irradiation devices which is to be monitored by the beam detection processing/control unit. The selector is controlled such that the selector establishes connection with the irradiation device in the selected one treatment room to which the charged particle beam is transported through the beam line. The system configuration can be simplified while maintaining the operation efficiency.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a particle beam therapy system in whicha charged particle beam of protons or carbon ions is irradiated to theaffected part in the body of a patient for treatment, and to a controlsystem for particle beam therapy. More particularly, the presentinvention relates to a particle beam therapy system having a pluralityof treatment rooms, and a control system for such a particle beamtherapy system.

2. Description of the Related Art

There is known a therapy method of irradiating a charged particle beamof protons or carbon ions to the affected part in the body of a patient,e.g., the cancer, for treatment. A large-scaled one of therapy systemsfor use with such a therapy method comprises a charged particle beamgenerator, a beam line, and a plurality of treatment rooms. A chargedparticle beam accelerated by the charged particle beam generatorreaches, through the beam line, an irradiation device installed in arotating gantry within one treatment room selected from among theplurality of treatment rooms, and is irradiated to the affected part ofthe patient body lying on a treatment bed from a nozzle of theirradiation device (see, e.g., Patent Reference 1; JP,A 11-501232).

SUMMARY OF THE INVENTION

Generally, a control system for the above-mentioned known therapy systemhaving a plurality of treatment rooms comprises a central controller forperforming supervisory control of the overall therapy system, atreatment planning system in which a treatment plan database is stored,a central interlock device for stopping the irradiation, e.g., when anyabnormality is detected, an accelerator controller for controllingextraction and stop of a charged particle beam from the charged particlebeam generator, a magnet power supply controller for performing powersupply control for magnets disposed in predetermined positions withinthe charged particle beam generator and the beam line, variouscontrollers installed in each of the treatment rooms, and a monitoringfunction device installed in each of the treatment rooms and monitoringthe state of the charged particle beam being irradiated from theirradiation device.

The controllers installed in each of the treatment rooms include agantry controller for controlling the rotation of a rotating gantry, abed controller for controlling the movement of a treatment bed,irradiation nozzle controllers for controlling those units of equipmentmounted in the irradiation device which are used for forming anirradiation field, such as an SOBP forming device and a boluscollimator, and an irradiation controller for controlling the gantrycontroller, the bed controller and the irradiation nozzle controllers ina supervisory manner.

The monitoring function device installed in each of the treatment roomshas not only the function of determining whether the beam state duringirradiation is within a preset allowable range, thereby detecting anabnormality if the beam state is outside the allowable range, but alsothe function of determining whether the dose has reached a preset value,thereby detecting attainment of the target dose when the dose hasreached the preset value. When an abnormality of the dose attainment isdetected by the monitoring function device, the beam extraction from thecharged particle beam generator is stopped.

In the therapy system having a plurality of treatment rooms, the chargedparticle beam extracted from the charged particle beam generator isusually irradiated in only one of the treatment rooms and is neverirradiated in the plurality of treatment rooms at the same time. Takinginto account that usual situation, it is conceivable to employ thecontrollers and the monitoring function device, which have been so farinstalled in each treatment room, in common with the plurality oftreatment rooms instead of installing them in each treatment room. Morespecifically, in the therapy system having a plurality of treatmentrooms, the therapy is generally progressed such that the irradiation isperformed in one selected treatment room, while positioning of thepatient, setting of the irradiation field forming equipment in theirradiation device, etc. are performed in the next treatment room. It istherefore can be said that the gantry controller for controlling therotation of the rotating gantry, the bed controller for controlling themovement of the treatment bed, the irradiation nozzle controllers forcontrolling the irradiation field forming equipment mounted in theirradiation device, and the irradiation controller for controlling thosecontrollers in a supervisory manner are preferably installed in each ofthe treatment rooms in consideration of the operation efficiency of thetherapy system. On the other hand, of the above-mentioned unitsinstalled in each treatment room, the monitoring function device formonitoring the beam state is not necessarily required to be installed ineach treatment room because it serves to monitor the beam state duringirradiation and is not used in the other treatment rooms than that underirradiation. Also, the monitoring function device does not take part inthe positioning of the patient and setting of the irradiation fieldforming equipment. Accordingly, sharing the monitoring function deviceby a plurality of treatment rooms will not lead to a reduction in theoperation efficiency of the therapy system.

Thus, the known therapy system is still susceptible to simplificationbecause of having a control system configured such that the monitoringfunction device for monitoring the beam state during irradiation isinstalled in each treatment room in spite of being sharable by aplurality of treatment rooms.

In view of the above-mentioned problem with the related art, an objectof the present invention is to provide a particle beam therapy systemand a control system for particle beam therapy, which can simplify asystem configuration while maintaining the operation efficiency.

To achieve the above object, the present invention provides a particlebeam therapy system for irradiating a charged particle beam to anaffected part of the body for treatment, wherein the therapy systemcomprises a charged particle beam generator for generating the chargedparticle beam; irradiation devices installed respectively in a pluralityof treatment rooms and irradiating the charged particle beam; a beamline for transporting the charged particle beam extracted from thecharged particle beam generator to the irradiation device in selectedone of the plurality of treatment rooms; a monitoring unit formonitoring a beam state of the charged particle beam in one of theirradiation devices; a selector for switchably selecting one of theirradiation devices which is to be monitored by the monitoring unit; anda first control unit for controlling the selector such that the selectorestablishes connection with the irradiation device in the selected oneof the plurality of treatment rooms to which the charged particle beamis transported through the beam line.

With those features, since the irradiation device to be monitored by themonitoring unit is selected by the selector in a switching manner andthe first control unit controls the selector such that the selectorestablishes connection with the irradiation device in the selected oneof the plurality of treatment rooms to which the charged particle beamis transported through the beam line, the monitoring unit can be sharedby a plurality of treatment rooms. As a result, the system configurationcan be simplified.

According to the present invention, it is possible to simplify thesystem configuration while maintaining the operation efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall block diagram of a particle beam therapy systemaccording to a first embodiment of the present invention;

FIG. 2 is a schematic view showing a general equipment configuration ofan irradiation device of the passive irradiation type shown in FIG. 1;

FIG. 3 is a block diagram showing a flow of control signals in a controlsystem during operation of the particle beam therapy system according tothe first embodiment of the present invention;

FIG. 4 is a flowchart of the functions executed by a central controllerand a beam detection processing/control unit for determining whether theswitching operation of a selector is normally completed;

FIG. 5 is a chart showing the functions executed by the centralcontroller and the beam detection processing/control unit fordetermining whether the switching operation of the selector is normallycompleted;

FIG. 6 is an overall block diagram of a particle beam therapy system ofComparative Example 1 in which a control system includes a beamdetection processing/control unit in each treatment room;

FIG. 7 is an overall block diagram of the particle beam therapy systemaccording to the first embodiment of the present invention;

FIG. 8 is an overall block diagram of a particle beam therapy systemaccording to a second embodiment of the present invention;

FIG. 9 is a schematic view showing a general equipment configuration ofan irradiation device with scanning irradiation shown in FIG. 8;

FIG. 10 is an overall block diagram of a particle beam therapy systemaccording to a third embodiment of the present invention;

FIG. 11 is an overall block diagram of a particle beam therapy system ofComparative Example 2 in which a control system includes a beamdetection processing/control unit in each treatment room;

FIG. 12 is an overall block diagram of the particle beam therapy systemaccording to the third embodiment of the present invention;

FIG. 13 shows a modification of the particle beam therapy system, shownin FIG. 12, in which one treatment room for passive irradiation isreplaced with a treatment room for scanning irradiation;

FIG. 14 is an overall block diagram of a particle beam therapy systemaccording to a fourth embodiment of the present invention; and

FIG. 15 shows a modification of the particle beam therapy system, shownin FIG. 14, in which a control/monitoring panel is partly shared by aplurality of treatment rooms.

REFERENCE NUMERALS

-   1 charged particle beam generator-   2 beam line-   3A,3B irradiation device-   4A,4B irradiation device-   7A,7B treatment room-   8A,8B treatment room-   19 power supply controller (beam line controller)-   25,33 profile monitor (detector)-   29 energy monitor (detector)-   30 flatness monitor (detector)-   31,38 dose monitor (detector)-   34,35 scanning magnets-   37 spot position monitor (detector)-   42 display monitor (display)-   44 operating/monitoring panel (display)-   55 central controller (determining unit)-   57 central interlock device (second control unit and third control    unit)-   66 beam detection processing/control unit (monitoring unit, first    control unit, and determining unit)-   67 beam detection processing/control unit (monitoring unit, first    control unit, determining unit, and scan stroke control unit)-   70,71 selector-   100 particle beam therapy system-   110 control system-   135 beam detection processing/control unit (monitoring unit, first    control unit, and determining unit)-   136 beam detection processing/control unit (monitoring unit, first    control unit, determining unit, and scan stroke control unit)-   137 beam detection processing/control unit (monitoring unit, first    control unit, and determining unit)-   140 selector-   300 particle beam therapy system-   310 control system-   400 particle beam therapy system-   410 control system-   600 particle beam therapy system-   610 control system

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention will be described in detail belowwith reference to the drawings.

First Embodiment

A particle beam therapy system according to one preferred embodiment ofthe present invention will be described as a first embodiment withreference to FIG. 1. in the illustrated practical form, a particle beamtherapy system 100 of this first embodiment is constructed as a protonbeam therapy system. The particle beam therapy system 100 comprises acharged particle beam generator 1, a beam line 2 connected to thecharged particle beam generator 1 and extending downstream from it, anda plurality (two in this embodiment) of treatment rooms 7A, 7B. Aplurality (two in this embodiment) of irradiation devices (i.e.,irradiation field forming devices) 3A, 3B are installed in the treatmentrooms 7A, 7B in one-to-one relation.

The charged particle beam generator 1 comprises an ion source (notshown), a pre-stage accelerator (e.g., a linear accelerator) 11, and asynchrotron 12 as a main accelerator. Ions (e.g., protons (or carbonions)) generated in the ion source are accelerated by the pre-stageaccelerator 11, and an ion beam (charged particle beam) exiting thepre-stage accelerator 11 enters the synchrotron 12. The ion beam havingentered the synchrotron 12 circulates within the synchrotron 12, andafter being accelerated to a preset level of energy (e.g., 100-200 MeV),the ion beam is extracted from the synchrotron 12. Operations of thepre-stage accelerator 11 and the synchrotron 12 are controlled by anaccelerator controller 13.

The ion beam extracted from the synchrotron 12 is transported toselected one of the treatment rooms 7A, 7B through the beam line 2. Thebeam line 2 includes switching magnets (bending magnets) 14, 15. The ionbeam introduced to the beam line 2 is selectively transported to one ofthe treatment rooms 7A, 7B depending on the presence or absence of abending action that is effectuated with switching-over betweenexcitation and non-excitation of the switching magnets 14, 15. Numeral18 denotes a magnet power supply for making switching-over betweenexcitation and non-excitation of various magnets in the beam line 2,including the switching magnets 14, 15, and 19 denotes a power supplycontroller (beam line controller) for controlling the magnet powersupply 18.

A downstream end of the beam line 2 on the treatment room side isconnected to each of the irradiation devices 3A, 3B mounted torespective rotating gantries (not shown) which are installed in thetreatment rooms 7A, 7B. In each of the treatment rooms 7A, 7B, a patient20 is lying on a treatment bed 21 positioned in a treatment cage (notshown) that is formed inside the rotating gantry. The ion beam exitingthe irradiation device 3A or 3B is irradiated to the affected part (notshown) in the body of the patient 20.

The irradiation devices 3A, 3B are each of the passive irradiation typein which the ion beam is scattered by a scatterer and the scattered ionbeam is shaped by a collimator in match with the shape of the affectedpart (cancer) in the patient body, followed by irradiation to thecancer. FIG. 2 schematically shows a general equipment configuration ofeach of the irradiation devices 3A, 3B.

As shown in FIG. 2, each of the passive irradiation devices 3A, 3Bincludes a profile monitor (detector) 25 for measuring the centroid andwidth of the ion beam entering the irradiation device 3A, 3B from thebeam line 2, a first scatterer 26 for scattering the beam, an SOBP(Spread-Out Bragg Peak) forming device (e.g., a ridge filter or a rangemodulation wheel) 27, a second scatterer 28, an energy monitor(detector) 29 for measuring an energy amount of the irradiation beam, aflatness monitor (detector) 30 for measuring uniformity of theirradiated beam in a direction perpendicular to the direction of travelof the beam, a dose monitor (detector) 31 for detecting the dose, and abolus collimator 32 for adjusting the range of the ion beam and theshape of an irradiation field in the direction perpendicular to thedirection of travel of the beam to be matched with a target shape. Thoseunits 25 to 32 are mounted in the irradiation device in the mentionedorder from the upstream side in the direction of travel of the beam.

Returning to FIG. 1, treatment control rooms 40A, 40B where theoperations necessary for the treatment, etc. are carried out areinstalled respectively near the treatment rooms 7A, 7B. Each of thetreatment control rooms 40A, 40B includes a display monitor (displayunit) 42 and an operating/monitoring panel (display unit) 44 which areused to display the treatment situation and beam information of the ionbeam, such as the dose, and also includes a console 49 provided with anirradiation start button 46 for starting the irradiation, an irradiationstop button 47 for stopping the irradiation, and a beam request button48 for issuing a request for the beam irradiation to the chargedparticle beam generator 1.

A control system 110 provided in the particle beam therapy system 100 ofthis embodiment will be described below.

The control system 110 comprises a central controller (determining unit)55 for performing supervisory control of the entirety of the therapysystem 100, a treatment planning system 56 in which a treatment plandatabase is stored, a central interlock device (second control unit andthird control unit) 57 for stopping the irradiation, e.g., when anyabnormality of the beam is detected in the irradiation devices 3A, 3B,an accelerator controller 13 for performing control of the synchrotron12, and the above-mentioned power supply controller 19 for controlling apower supply for the magnets in the beam line 2.

Furthermore, the control system 110 includes, in the treatment rooms 7A,7B in one-to-one relation, gantry controllers 58A, 58B, bed controllers60A, 60B, irradiation nozzle controllers 62A, 62B, and irradiationcontrollers 64A, 64B for controlling those corresponding threecontrollers in a supervisory manner. In each treatment room 7A, 7B, therotating gantry is rotated by controlling the rotation of a motor (notshown) by the gantry controller 58A, 58B, and the treatment bed 21 ismoved and controlled by the bed controller 60A, 60B. Also, of theequipment mounted in each irradiation device 3A, 3B, those units forforming the irradiation field, such as the first and second scatterers26, 28, the SOBP forming device 27 and the bolus collimator 32, arecontrolled by the irradiation nozzle controller 62A, 62B.

More specifically, when positioning the patient 20, a doctor (or anoperator) standing near the patient 20 in each treatment room 7A, 7Bmanipulates a nearby operating unit (e.g., a pendant) 65 connected tothe irradiation controller 64A, 64B, whereupon a control start signal ora control stop signal is transmitted to corresponding one of theabove-mentioned three controllers through the irradiation controller64A, 64B. For example, when the control start signal for the rotatinggantry is outputted from the nearby operating unit 65 in the treatmentroom 7A, the central controller 55 takes in rotational angle informationfor the rotating gantry with regards to the patient 20 from thetreatment plan information stored in the treatment planning system 56and transmits the taken-in rotational angle information to the gantrycontroller 58A through the irradiation controller 64A. The gantrycontroller 58A rotates the rotating gantry based on the rotational angleinformation.

In addition, the control system 110 comprises a beam detectionprocessing/control unit (monitoring unit, first control unit anddetermining unit) 66 for both the treatment rooms 7A, 7B. The functionsof the beam detection processing/control unit 66 will be described belowwith reference to FIG. 2.

As shown in FIG. 2, of the equipment mounted in each passive irradiationdevice 3A, 3B, those units for forming the irradiation field, i.e., thefirst and second scatterers 26, 28, the SOBP forming device 27, and thebolus collimator 32, are controlled by the irradiation nozzle controller62A, 62B. Because those units are mounted in match with the irradiationtarget for each patient, the irradiation nozzle controller 62A, 62Bmakes monitoring to avoid a possibility that a false unit is mounted.

On the other hand, the beam information obtained from those detectorsamong the equipment mounted in the irradiation device 3A, 3B which areused to detect the beam information of the ion beam under irradiation,i.e., the profile monitor 25, the energy monitor 29, the flatnessmonitor 30, and the dose monitor 31, is taken into the beam detectionprocessing/control unit 66. The beam detection processing/control unit66 has the functions of monitoring the beam information obtained bythose detectors. More specifically, the beam detectionprocessing/control unit 66 includes a control/processing section 66 afor taking in the information measured by the profile monitor 25,computing the centroid and width of the ion beam, and detecting anabnormality of the centroid or width when the computed result exceeds anallowable value, a control/processing section 66 b for computing anenergy distribution from the information measured by the energy monitor29 and detecting an abnormality of the energy distribution when thecomputed result exceeds an allowable value, a control/processing section66 c for computing flatness of the ion beam from the informationmeasured by the flatness monitor 30 and detecting an abnormality of thebeam flatness when the computed result exceeds an allowable value, and acontrol/processing section 66 d for monitoring the dose from theinformation measured by the dose monitor 31 and detecting attainment ofthe target dose when the monitored does has reached a preset value.

When any beam abnormality is detected by the thus-constructed beamdetection processing/control unit 66 (exactly speaking, by thecontrol/processing sections 66 a to 66 c), the beam detectionprocessing/control unit 66 outputs an abnormality signal to the centralinterlock device 57, and the central interlock device 57 having receivedthe abnormality signal outputs an irradiation stop signal to theaccelerator controller 13. Then, an on/off switch (not shown) providedin the synchrotron 12 is opened under control of the acceleratorcontroller 13, whereupon the supply of RF waves to an RF knockoutelectrode (not shown) is stopped and the extraction of the ion beam fromthe synchrotron 12 is also stopped. When the attainment of the targetdose is detected by the beam detection processing/control unit 66(exactly speaking, by the control/processing section 66 d), the beamdetection processing/control unit 66 outputs a dose attainment signal tothe central controller 55, and the central controller 55 having receivedthe dose attainment signal outputs a beam irradiation end signal to theaccelerator controller 13, whereby the extraction of the ion beam fromthe synchrotron 12 is stopped in the same way as that described above.As a result, excess irradiation and false irradiation to the patient 20can be avoided.

The control system 110 includes one beam detection processing/controlunit 66 for the two irradiation devices 3A, 3B, and one of those twoirradiation devices from which the beam detection processing/controlunit 66 obtains the beam information (i.e., the irradiation device as amonitoring target) is selected by a selector 70. In other words, thebeam detection processing/control unit 66 is shared by the irradiationdevices 3A, 3B (or the treatment rooms 7A, 7B).

The selector 70 includes a switching circuit 70 a for switching over theprofile monitors 25, 25 of the irradiation devices 3A, 3B, a switchingcircuit 70 b for switching over the energy monitors 29, 29 of theirradiation devices 3A, 3B, a switching circuit 70 c for switching overthe flatness monitors 30, 30 of the irradiation devices 3A, 3B, and aswitching circuit 70 d for switching over the dose monitors 31, 31 ofthe irradiation devices 3A, 3B. Those switching circuits 70 a to 70 dare all always turned to the same side when switched over, without beingirregularly turned to the different sides.

The switching operation of the selector 70 is performed by the beamdetection processing/control unit 66 (more exactly speaking, theswitching circuits 70 a to 70 d of the selector 70 are switched by thecontrol/processing sections 66 a to 66 d of the beam detectionprocessing/control unit 66, respectively) so as to establish connectionwith the selected treatment room (i.e., the treatment room to which theion beam is transported through the beam line 2). The switching sequencewill be described below with reference to FIG. 3. FIG. 3 is a blockdiagram showing a flow of control signals in a control system 110 duringoperation of the particle beam therapy system 100 according to thisembodiment. In the following description, it is assumed that thetreatment room 7A is the selected treatment room (i.e., the treatmentroom where the irradiation for treatment is performed).

Using the nearby operating unit 65, a doctor (or an operator) makespositioning of the patient 20 by driving the rotating gantry and thetreatment bed 21 under control of the gantry controller 58A and the bedcontroller 60A through the irradiation controller 64A, and also makessetting of the equipment in the irradiation device 3A, i.e., the firstand second scatterers 26, 28, the SOBP forming device 27, and the boluscollimator 32, under control of the irradiation nozzle controller 62A.Upon completion of the patient positioning and the equipment setting,the irradiation controller 64A outputs a patient positioning end signal72 to an AND circuit 73 in the central controller 55. On the other hand,when a doctor (or an operator) in the treatment control room 40Aoperates a beam request button 48 on the console 49, a beam requestsignal 74 is outputted from the console 49 to the AND circuit 73 in thecentral controller 55.

When the patient positioning end signal 72 and the beam request signal74 are both inputted to the AND circuit 73 and the AND logical conditionis satisfied, the AND circuit 73 outputs a power supply switching signal75 to the power supply controller 19. Responsively, the power supplycontroller 19 switches over the power supply for the switching magnet 14in the beam line 2 through the magnet power supply 18. As a result, abeam path toward the treatment room 7A is formed, whereby the selectionof the treatment room is completed. Upon completion of the selection ofthe treatment room, the power supply controller 19 outputs a switchingend signal 76 to an AND circuit 77 in the central controller 55.

When the switching end signal 76 and the power supply switching signal75 from the AND circuit 73 are both inputted to the AND circuit 77 andthe AND logical condition is satisfied, the AND circuit 77 outputs atreatment room selection end signal 78 to the beam detectionprocessing/control unit 66. Responsively, the beam detectionprocessing/control unit 66 outputs a monitor switching signal 79 to theselector 70 and controls the selector 70 such that the irradiationdevice 3A (or the treatment room 7A) is selected as a connectiondestination. Upon completion of the switching operation, the selector 70outputs an answer back signal 69 to the beam detectionprocessing/control unit 66. Based on the answer back signal 69, the beamdetection processing/control unit 66 determines whether the switchingoperation of the selector 70 has been normally completed (as describedlater in detail). If the normal switching operation is determined, thebeam detection processing/control unit 66 outputs a switching end signal80 to an AND circuit 81 in the central controller 55.

Also, when the switching end signal 76 and the power supply switchingsignal 75 from the AND circuit 73 are both inputted to the AND circuit77 and the AND logical condition is satisfied, the AND circuit 77outputs, in addition to the treatment room selection end signal 78, anaccelerator preparation start signal 82 to the accelerator controller13. Responsively, the accelerator controller 13 performs setting andpreparation of the equipment constituting the charged particle beamgenerator 1, such as the pre-stage accelerator 11 and the synchrotron12. Upon completion of the setting and the preparation, the acceleratorcontroller 13 outputs an accelerator preparation end signal 83 to theAND circuit 81 in the central controller 55.

The AND circuit 81 receives the accelerator preparation end signal 83from the accelerator controller 13, the switching end signal 80 from thebeam detection processing/control unit 66, the treatment room selectionend signal 78 from the AND circuit 77, and a switching normal signal 68(described later in detail) outputted when it is determined by acomparing and determining section 96 (see FIG. 5 described later) of thecentral controller 55 that the switching operation of the selector 70has been normally completed. Then, when the AND logical condition issatisfied, the AND circuit 81 outputs an irradiation start preparationend signal 84 to an AND circuit 85 based on judgment that theirradiation start preparations for the treatment room 7A have beencompleted.

On the other hand, when the doctor (or the operator) in the treatmentcontrol room 40A operates an irradiation start button 46 on the console49, an irradiation start signal 86 is outputted from the console 49 tothe AND circuit 85 in the central controller 55.

When the irradiation start preparation end signal 84 from the ANDcircuit 81 and the irradiation start signal 86 from the console 49 areboth inputted to the AND circuit 85 and the AND logical condition issatisfied, the AND circuit 85 outputs an irradiation start signal 87 tothe accelerator controller 13 to start the irradiation. Morespecifically, the on/off switch (not shown) provided in the synchrotron12 is closed by the accelerator controller 13, whereupon the supply ofRF waves to the RF knockout electrode (not shown) is started and theextraction of the ion beam from the synchrotron 12 is also started.

During the beam irradiation, the information of the ion beam underirradiation is detected by the profile monitor 25, the energy monitor29, the flatness monitor 30, and the dose monitor 31, which are mountedin the irradiation device 3A, and is inputted to the beam detectionprocessing/control unit 66 through the selector 70. The beam detectionprocessing/control unit 66 monitors the detected information. Morespecifically, it determines whether each item of the beam informationdetected by the profile monitor 25, the energy monitor 29 and theflatness monitor 30 is within a predetermined allowable range, andwhether the dose detected by the dose monitor 31 has reached apredetermined dose. Further, the beam detection processing/control unit66 outputs a beam information signal 88 to the display monitor 42 in thetreatment control room 40A. As a result, the beam information duringirradiation is displayed on the display monitor 42.

When the detected dose reaches the preset dose, the beam detectionprocessing/control unit 66 outputs a dose attainment signal 89 to an ORcircuit 90 in the central controller 55. On the other hand, when thedoctor (or the operator) in the treatment control room 40A operates anirradiation stop button 47 on the console 49, an irradiation stop signal91 is outputted from the console 49 to the OR circuit 90 in the centralcontroller 55.

When either one of the irradiation stop signal 91 from the console 49and the dose attainment signal 89 from the beam detectionprocessing/control unit 66 is inputted to the OR circuit 90, the ORcircuit 90 outputs an irradiation end signal 92 to the acceleratorcontroller 13 to stop the irradiation. More specifically, the on/offswitch (not shown) provided in the synchrotron 12 is opened by theaccelerator controller 13, whereupon the supply of RF waves to the RFknockout electrode (not shown) is stopped and the extraction of the ionbeam from the synchrotron 12 is also stopped.

When, during the irradiation, the beam detection processing/control unit66 determines that any item of the beam information has exceeded theallowable range, the beam detection processing/control unit 66 outputsan abnormality signal 93 to an OR circuit 94 in the central interlockdevice 57. Responsively, the central interlock device 57 outputs anirradiation stop signal 95 to the accelerator controller 13, whereuponthe extraction of the ion beam from the synchrotron 12 is stopped undercontrol of the accelerator controller 13.

Although the sequence for selecting the treatment room is omitted in theabove description, the central controller 55 may be designed, forexample, to have the function of selecting one of the treatment roomsfrom which the beam request signal 74 issued from the console 49 in thecorresponding treatment room 40A, 40B has been inputted at the earliesttiming in the state where the positioning of the treatment room has beencompleted.

While a description is omitted above for the sake of simplicity, each ofthe central controller 55 and the beam detection processing/control unit66 in the therapy system of this embodiment has the function ofdetermining whether the switching operation of the selector 70 has beennormally completed. Unless it is determined by both the centralcontroller 55 and the beam detection processing/control unit 66 that theswitching operation of the selector 70 has been normally completed, theirradiation start preparation end signal 84 is never outputted from theAND circuit 81 to the AND circuit 85. FIG. 4 shows a flow of thatdetermining function. In FIG. 4, the sequence of processing executed bythe units (i.e., the central controller 55, the beam detectionprocessing/control unit 66, and the selector 70) is shown successivelyin the vertical direction starting from the top.

First, the treatment room selection end signal 78 is outputted from thecentral controller 55 (exactly speaking, the AND circuit 77) to the beamdetection processing/control unit 66 (step 101). In response to thetreatment room selection end signal 78 thus inputted, the beam detectionprocessing/control unit 66 outputs the monitor switching signal 79 tothe selector 70 (step 102). The target to be monitored by the beamdetection processing/control unit 66 is switched over in response to themonitor switching signal 79 inputted to the selector 70 (step 103).

Upon completion of the switching operation, the selector 70 outputs theanswer back signal 69 to the beam detection processing/control unit 66.The beam detection processing/control unit 66 compares the monitorswitching signal 79, which has been outputted as a command value, withthe answer back signal 69 inputted as a response value, and determineswhether the switching operation has been normally completed (step 104).If the treatment rooms represented by those two signals are matched witheach other, this is regarded as indicating that the switching operationhas been normally completed (step 105). Only after thus determining thatthe switching operation has been normally completed, the beam detectionprocessing/control unit 66 outputs the switching end signal 80,described above with reference to FIG. 3, to the AND circuit 81 in thecentral controller 55. Conversely, if the treatment rooms represented bythe two signals are mismatched, this is regarded as indicating that theswitching operation has not been normally completed (step 106).

Also, the answer back signal 69 from the selector 70 is outputted to thecomparing and determining section 96 (see FIG. 5 described later) of thecentral controller 55 in addition to the beam detectionprocessing/control unit 66. The comparing and determining section 96compares the treatment room selection end signal 78, which has beenoutputted as a command value, with the answer back signal 69 inputted asa response value, and determines whether the switching operation hasbeen normally completed (step 107). If the treatment rooms representedby those two signals are matched with each other, this is regarded asindicating that the switching operation has been normally completed(step 108), and the comparing and determining section 96 outputs theswitching normal signal 68 to the AND circuit 81. Conversely, if thetreatment rooms represented by the two signals are mismatched, this isregarded as indicating that the switching operation has not beennormally completed (step 109).

In such a way, if it is determined by both the beam detectionprocessing/control unit 66 and the central controller 55 that theswitching operation has been normally completed, final determination ismade on the normal completion of the switching operation (step 111). Inresponse to the final determination, as described above with referenceto FIG. 3, the irradiation start preparation end signal 84 is outputtedfrom the AND circuit 81 to the AND circuit 85 in the central controller55 to progress the preparations for start of the irradiation. On theother hand, if the abnormal switching is determined by at least one ofthe beam detection processing/control unit 66 and the central controller55, this is regarded as indicating that the switching operation of theselector 70 has not been normally completed, and whether to retry theswitching operation or not is selected by the beam detectionprocessing/control unit 66 (step 112). If the switching operation is notretried, the irradiation start preparation end signal 84 is notoutputted from the AND circuit 81 to the AND circuit 85, and thereforethe irradiation in the selected treatment room is disabled (step 113).

Incidentally, the above-described monitoring of the switching state ofthe selector 70 by the central controller 55 and the beam detectionprocessing/control unit 66 is performed at all times even during thebeam irradiation. Should the abnormal switching is determined during theirradiation, the central controller 55 outputs the abnormality signal tothe central interlock device 57, thereby stopping the extraction of theion beam from the synchrotron 12 through the accelerator controller 13.

FIG. 5 shows, in more detail, the above-described switching determiningfunction executed by the central controller 55 and the beam detectionprocessing/control unit 66.

As shown in FIG. 5, the switching circuits 70 a to 70 d included in theselector 70 are each usually held in a position 0 corresponding to astate where neither the treatment room 7A nor the treatment room 7B areselected. When each switching circuit is switched over to a position 1,the corresponding detectors in the treatment room 7A (or the irradiationdevice 3A) are selected, and when it is switched over to a position 2,the corresponding detectors in the treatment room 7B (or the irradiationdevice 3B) are selected.

The central controller 55 outputs a command value M (corresponding tothe above-mentioned treatment room selection signal 78) to the beamdetection processing/-control unit 66. The command value M is inputtedto each of the control/processing sections 66 a to 66 d of the beamdetection processing/control unit 66. Herein, M=1 represents theselection of the treatment room 7A, and M=2 represents the selection ofthe treatment room 7B. The control/processing sections 66 a to 66 d ofthe beam detection processing/control unit 66, to which the commandvalue M has been inputted, apply the command value M to the switchingcircuits 70 a to 70 d of the selector 70, thereby performing theswitching operations.

Selection values N from the detectors 25, 29, 30 and 31 on the side ofthe selected treatment room (i.e., the treatment room 7A in FIG. 5) areinputted to the switching circuits 70 a to 70 d of the selector 70,respectively. The switching circuits 70 a to 70 d output the selectionvalues N (each corresponding to the above-mentioned answer back signal69) to not only the control/processing sections 66 a to 66 d of the beamdetection processing/control unit 66, but also to the comparing anddetermining section 96 of the central controller 55. Each of thecontrol/processing sections 66 a to 66 d of the beam detectionprocessing/control unit 66 compares the command value M with theselection value N and determines a match between M and N. Also, thecomparing and determining section 96 of the central controller 55compares the selection values N inputted from the switching circuits 70a to 70 d with the corresponding command values M and determines a matchbetween M and N.

If the control/processing sections 66 a to 66 d of the beam detectionprocessing/control unit 66 determines a match between M and N,respective match signals are outputted to an AND circuit 115. When thematch signals are inputted from all the control/processing sections 66 ato 66 d to the AND circuit 115 and the AND logical condition issatisfied, the AND circuit 115 outputs the above-mentioned switching endsignal 80 to an AND circuit 81 in the central controller 55. On theother hand, if any of the control/processing sections 66 a to 66 ddetermines a mismatch between M and N, a mismatch signal 118 isoutputted from an OR circuit 116 to an OR circuit 117 in the centralcontroller 55.

Further, if the comparing and determining section 96 of the centralcontroller 55 determines a match between the command value M and theselection value N inputted from corresponding one of the switchingcircuits 70 a to 70 d, a match signal is outputted to an AND circuit119. When the match signals corresponding to all the switching circuits70 a to 70 d are inputted to the AND circuit 119 and the AND logicalcondition is satisfied, the AND circuit 119 outputs the above-mentionedswitching normal signal 68 to the AND circuit 81. On the other hand, ifit is determined that any of the selection values N inputted from theswitching circuits 70 a to 70 d is mismatched with the correspondingcommand value M, a mismatch signal 121 is outputted from an OR circuit120 to the OR circuit 117.

When the switching normal signal 68 from the AND circuit 119 and theswitching end signal 80 from the AND circuit 115 are both inputted tothe AND circuit 81 and the AND logical condition is satisfied, this isregarded as indicating that the switching operation has been normallycompleted, and the AND circuit 81 outputs the irradiation startpreparation end signal 84 to the AND circuit 85 to progress thepreparations for start of the irradiation, as described above. On theother hand, if the mismatch signal 118 from the OR circuit 116 or themismatch signal 121 from the OR circuit 120 is inputted to the ORcircuit 117, this is regarded as indicating a switching abnormality, andthe irradiation in the treatment room 7A is disabled.

If any of the control/processing sections 66 a to 66 d of the beamdetection processing/control unit 66 and the comparing and determiningsection 96 of the central controller 55 determines that thecorresponding selection value N is 0, this is regarded as indicatingthat the system is under switching or the switching operation is notproperly performed, and the switching operation is repeated.

With the particle beam therapy system 100 of this embodiment, the systemconfiguration of the control system 110 can be simplified. This pointwill be described below with reference to Comparative Example 1.

FIG. 6 is an overall block diagram of a particle beam therapy system 200of Comparative Example 1. This therapy system 200 differs from thetherapy system 100 of the first embodiment in that a control system 210for the former includes beam detection processing/control units 66A, 66B(indicated by hatched areas) provided in one-to-one relation to thetreatment rooms 7A, 7B (or the irradiation devices 3A, 3B), and that theselector 70 is not provided in the former. The remaining configurationis the same as that of the control system 100.

In the therapy system having a plurality of treatment rooms to whichComparative Example 1 and this embodiment are applied, as describedabove, the ion beam extracted from the charged particle beam generator 1is irradiated in only one treatment room and is never irradiated in aplurality of treatment rooms at the same time. Therefore, the beamdetection processing/control units 66A, 66B provided in one-to-onerelation to the treatment rooms 7A, 7B in the therapy system 200 ofComparative Example 1 are not necessarily required to be installed inthe respective treatment rooms 7A, 7B because they serve to monitor thebeam state during irradiation and are not used in the other treatmentrooms than that under irradiation. Also, the beam detectionprocessing/control units 66A, 66B do not take part in the positioning ofthe patient 20 and the setting of the irradiation field formingequipment, which are performed during the irradiation in the otherselected treatment room. Accordingly, sharing the beam detectionprocessing/control units 66A, 66B by the treatment rooms 7A, 7B will notlead to a reduction in the operation efficiency of the therapy system.Thus, the therapy system 200 of Comparative Example 1 is stillsusceptible to simplification in the configuration of the controlsystem.

In contrast, with the control system 110 for the therapy system 100 ofthis embodiment, the beam detection processing/control unit 66 is sharedby the treatment rooms 7A, 7B, as shown in FIG. 7, by providing theselector 70 to be able to switch over the irradiation device monitoredby the beam detection processing/control unit 66 from one to the other,and by controlling the selector 70 such that the selector selectivelyestablishes connection with the irradiation device in the treatment roomto which the ion beam is to be transported through the beam line 2. Sucha configuration means that the two beam detection processing/controlunits 66A, 66B indicated by hatched areas in FIG. 6 are replaced withthe one beam detection processing/control unit 66 and the simpleselector 70, which are indicated by hatched areas in FIG. 7. Therefore,the system configuration can be simplified as compared with the controlsystem 210 of Comparative Example 1. In addition, the beam detectionprocessing/control unit 66 does not take part in the positioning of thepatient 20 and the setting of the irradiation field forming equipment,which are performed during in the treatment room not under irradiation,i.e., during the irradiation in the other selected treatment room. Thegantry controllers 58A, 58B, the bed controllers 60A, 60B, theirradiation nozzle controllers 62A, 62B, and the irradiation controllers64A, 64B, which are necessary for performing the preparations to startthe irradiation, are installed in each of the treatment rooms.Accordingly, the operation efficiency of the therapy system is notreduced.

Further, with the particle beam therapy system 100 of this embodiment,system extensibility can be improved. More specifically, when adding anew treatment room, for example, a new beam detection processing/controlunit must be installed in the case of the therapy system 200 ofComparative Example 1 described above with reference to FIG. 6. On theother hand, the therapy system 100 of this embodiment is adaptable forsuch an extension just by connecting a newly installed irradiationdevice to the selector 70 and adding a corresponding switching functionto the selector 70. It is therefore possible to easily add a newtreatment room and to improve the system extensibility.

While the above description has been made, by way example, in connectionwith the therapy system having two treatment rooms, the presentinvention is of course also applicable to a therapy system having threeor more treatment rooms. The above-mentioned effects of the therapysystem of this embodiment in simplifying the system configuration andimproving the system extensibility become more noticeable as the numberof treatment rooms increases.

Second Embodiment

A charged particle therapy system according to another preferredembodiment of the present invention will be described below as a secondembodiment with reference to FIG. 8. In contrast with the firstembodiment in which the present invention is applied to the therapysystem 100 having a plurality of treatment rooms for passiveirradiation, the present invention is applied to a therapy system havinga plurality of treatment rooms for scanning irradiation in this secondembodiment.

A charged particle therapy system 300 of this embodiment includestreatment rooms 8A, 8B in which are installed respectively irradiationdevices 4A, 4B of the scanning irradiation type scanning a fine beam andirradiating the scanned beam to the affected part in the body of thepatient 20. FIG. 9 schematically shows a general equipment configurationof each of the irradiation devices 4A, 4B.

As shown in FIG. 9, each of the scanning irradiation devices 4A, 4Bincludes a profile monitor (detector) 33 for measuring the centroid andwidth of the ion beam entering the irradiation device 4A, 4B from thebeam line 2, scanning magnets 34, 35 for bending the ion beam to aposition suitable for irradiation to a target, a scatterer 36 fordeciding the width of the irradiation beam, a spot position monitor(detector) 37 for measuring the centroid and width of the ion beam bentby the scanning magnets 34, 35, and a dose monitor (detector) 38 fordetecting the dose. Those units 33 to 38 are mounted in the irradiationdevice in the mentioned order from the upstream side in the direction oftravel of the beam.

A control system 310 for the therapy system 300 of this embodimentincludes a beam detection processing/control unit (monitoring unit,first control unit, determining unit, and scan stroke control unit) 67for both the treatment rooms 8A, 8B. The functions of the beam detectionprocessing/control unit 67 will be described below.

As shown in FIG. 9, of the equipment mounted in each scanningirradiation device 4A, 4B, the scatterer 36 for forming the irradiationfield is controlled by the above-mentioned irradiation nozzle controller63A, 63B. Because the scatterer 36 is mounted in match with theirradiation target, the irradiation nozzle controller 63A, 63B makesmonitoring to avoid a possibility that a false scatterer is mounted.

On the other hand, beam information obtained from those detectors amongthe equipment mounted in the irradiation device 4A, 4B which are used todetect the beam information of the ion beam under irradiation, i.e., theprofile monitor 33, the spot position monitor 37, and the dose monitor38, is taken into the beam detection processing/control unit 67. Thebeam detection processing/control unit 67 has not only the function ofdetermining whether each item of the beam information detected by thosedetectors is within a predetermined allowable range, but also thefunction of controlling the scanning magnets 34, 35. More specifically,the beam detection processing/control unit 67 includes acontrol/processing section 67 a for taking in the information measuredby the profile monitor 33, computing the centroid and width of the ionbeam, and detecting an abnormality of the centroid or width when thecomputed result exceeds an allowable value, a control/processing section67 b for comparing preset current values of the scanning magnets 34, 35with actually measured current values and controlling the scanningmagnets 34, 35 in accordance with the compared results, acontrol/processing section 67 c for computing the centroid and width ofthe scanned ion beam from the information measured by the spot positionmonitor 37 and detecting an abnormality of the ion beam when thecomputed results exceed respective allowable values, and acontrol/processing section 67 d for monitoring the dose from theinformation measured by the dose monitor 38 and detecting attainment ofthe target dose when the monitored does has reached a preset value. Whenthe beam abnormality or the dose attainment is detected by the beamdetection processing/control unit 67, the extraction of the ion beamfrom the synchrotron 12 is stopped in the same way as that in the beamdetection processing/control unit 66 described above.

Returning to FIG. 8, the control system 310 includes one beam detectionprocessing/control unit 67 for the two irradiation devices 4A, 4B, andone of those two irradiation devices, which is to be monitored by thebeam detection processing/control unit 67, is selected by a selector 71.In other words, the beam detection processing/control unit 67 is sharedby the irradiation devices 4A, 4B (or the treatment rooms 8A, 8B).

The selector 71 includes a switching circuit 71 a for switching over theprofile monitors 33, 33 of the irradiation devices 4A, 4B, a switchingcircuit 71 b for switching over the scanning magnets 34, 34 of theirradiation devices 4A, 4B, a switching circuit 71 c for switching overthe scanning magnets 35, 35 of the irradiation devices 4A, 4B, aswitching circuit 71 d for switching over the spot position monitors 37,37 of the irradiation devices 4A, 4B, and a switching circuit 71 e forswitching over the dose monitors 38, 38 of the irradiation devices 4A,4B. Those switching circuits 71 a to 71 e are all always turned to thesame side when switched over, without being irregularly turned to thedifferent sides.

The remaining configuration of the therapy system 300 of this embodimentis the same as that in the foregoing therapy system 100.

With the therapy system 300 of this embodiment, as with the firstembodiment described above, the system configuration can be simplifiedwhile maintaining the operation efficiency, and the system extensibilitycan be improved. In general, the scanning irradiation is required tohandle a larger number of input signals from the detectors and thereforeto use a more complicated beam detection processing/control unit thanthat used in the passive irradiation. For that reason, a greater effectcan be obtained in the case of applying the present invention to ascanning irradiation therapy system like this embodiment than in thecase of applying the present invention to a passive irradiation therapysystem like the first embodiment.

Third Embodiment

A charged particle therapy system according to still another preferredembodiment of the present invention will be described below as a thirdembodiment with reference to FIG. 10. In contrast with the first andsecond embodiments in which the present invention is applied to thetherapy system having a plurality of treatment rooms for the sameirradiation method, the present invention is applied to a therapy systemhaving a plurality of treatment rooms for the different irradiationmethods in this third embodiment.

A charged particle therapy system 400 of this embodiment is a systemincluding both the configuration of the therapy system 100 describedabove as the first embodiment and the configuration of the therapysystem 300 described above as the second embodiment. More specifically,the charged particle therapy system 400 has four treatment rooms, i.e.,treatment rooms 7A, 7B equipped with irradiation devices 3A, 3B of thepassive irradiation type and treatment rooms 8A, 8B equipped withirradiation devices 4A, 4B of the scanning irradiation type. Theequipment configuration of each of the irradiation devices 3A, 3B andthe irradiation devices 4A, 4B is the same as that in the first andsecond embodiments.

An ion beam extracted from a synchrotron 12 in a charged particle beamgenerator 1 is transported to selected one of the treatment rooms 7A,7B, 8A and 8B through a beam line 2. The beam line 2 includes switchingmagnets (bending magnets) 14 to 17. The ion beam introduced to the beamline 2 is selectively transported to one of the treatment rooms 7A, 7B,8A and 8B depending on switching-over between excitation andnon-excitation of the switching magnets 14 to 17 through a magnet powersupply 18. The magnet power supply 18 is controlled by a power supplycontroller 19.

Treatment control rooms 40A, 40B, 41A and 41B where the operationsnecessary for the treatment, etc. are carried out are installed near thetreatment rooms 7A, 7B, 8A and 8B, respectively. Each of the treatmentcontrol rooms 40A, 40B, 41A and 41B includes a display monitor 42, anoperating/-monitoring panel 44, and a console 49.

A control system 410 for the charged particle therapy system 400comprises a central controller 55, a treatment planning system 56, acentral interlock device 57, an accelerator controller 13, and the powersupply controller 19. Furthermore, the control system 410 includes, inthe treatment rooms 7A, 7B, 8A and 8B in one-to-one relation, gantrycontrollers 58A, 58B, 59A and 59B, bed controllers 60A, 60B, 61A and61B, irradiation nozzle controllers 62A, 62B, 63A and 63B, andirradiation controllers 64A, 64B, 65A and 65B for controlling thosecorresponding three controllers in a supervisory manner. In addition,the control system 410 includes a beam detection processing/control unit66 provided for the two treatment rooms 7A, 7B, and a beam detectionprocessing/control unit 67 provided for the two treatment rooms 8A, 8B.The configurations and functions of the beam detectionprocessing/control units 66, 67 are the same as those in the first andsecond embodiments. In other words, the beam detectionprocessing/control units 66, 67 monitor beam information in theirradiation devices 3A, 3B, 4A and 4B. If a beam abnormality isdetected, or if attainment of target dose is detected, the extraction ofthe ion beam from the synchrotron 12 is stopped, whereby excessirradiation and false irradiation to the patient 20 can be avoided.

The irradiation devices to be monitored by the beam detectionprocessing/control units 66, 67 are selected by the selectors 70, 71,respectively. The configurations and functions of the selectors 70, 71are the same as those in the first and second embodiments. The switchingoperations of the selectors 70, 71 are performed by the beam detectionprocessing/control units 66, 67 (more exactly speaking, switchingcircuits 70 a to 70 d of the selector 70 are switched respectively bycontrol/processing sections 66 a to 66 d of the beam detectionprocessing/control unit 66, and switching circuits 71 a to 71 e of theselector 71 are switched respectively by control/processing sections 67a to 67 d of the beam detection processing/control unit 67) so as toestablish connection with the selected treatment room (i.e., thetreatment room to which the ion beam is transported through the beamline 2). Whether the switching operation of the selector 70 has beennormally completed is determined by both the central controller 55(i.e., a comparing and determining section 96 therein) and the beamdetection processing/control unit 66, and whether the switchingoperation of the selector 71 has been normally completed is determinedby both the central controller 55 (i.e., the comparing and determiningsection 96 therein) and the beam detection processing/control unit 67.Unless the switching operation has been normally completed, theirradiation in the selected treatment room is stopped.

The remaining configuration of the therapy system 400 of this embodimentis the same as that of the therapy systems 100 and 300 described above.

With the particle beam therapy system 400 of this embodiment, the systemconfiguration of the control system 410 can be simplified. This pointwill be described below with reference to Comparative Example 2.

FIG. 11 is an overall block diagram of a particle beam therapy system500 of Comparative Example 2. This therapy system 500 differs from thetherapy system 400 of the third embodiment in that a control system 510for the former includes beam detection processing/control units 66A,66B, 67A and 67B (indicated by hatched areas) provided in one-to-onerelation to the treatment rooms 7A, 7B, 8A and 8B (or the irradiationdevices 3A, 3B, 4A and 4B), and that the selectors 70, 71 are notprovided in the former. The remaining configuration is the same as thatof the therapy system 400.

In contrast, with the control system 410 for the therapy system 400 ofthis embodiment, the beam detection processing/control unit 66 is sharedby the treatment rooms 7A, 7B and the beam detection processing/controlunit 67 is shared by the treatment rooms 8A, 8B, as shown in FIG. 12, byproviding the selector 70 to be able to switch over the irradiationdevice monitored by the beam detection processing/control unit 66 fromone to the other, providing the selector 71 to be able to switch overthe irradiation device monitored by the beam detectionprocessing/control unit 67 from one to the other, and by controlling theselectors 70, 71 such that the selector 70 or 71 selectively establishesconnection with the irradiation device in the treatment room to whichthe ion beam is to be transported through the beam line 2. Such aconfiguration means that the four beam detection processing/controlunits 66A, 66B, 67A and 67B indicated by hatched areas in FIG. 11 arereplaced with the two beam detection processing/control unit 66, 67 andthe simple selectors 70, 71, which are indicated by hatched areas inFIG. 12. Therefore, the system configuration can be simplified ascompared with the control system 510 of Comparative Example 2. Inaddition, the gantry controllers 58A, 58B, 59A and 59B, the bedcontrollers 60A, 60B, 61A and 61B, the irradiation nozzle controllers62A, 62B, 63A and 63B, and the irradiation controllers 64A, 64B, 65A and65B, which are necessary for performing the preparations to start theirradiation, are installed in each of the treatment rooms. Accordingly,the operation efficiency of the therapy system is not reduced.

Further, with the particle beam therapy system 400 of this embodiment,system flexibility and extensibility can be improved. This point will bedescribed below with reference to FIG. 13. FIG. 13 is an overall blockdiagram of a particle beam therapy system 400′ modified from theparticle beam therapy system 400 of this embodiment such that theirradiation method for the treatment room 7B is changed from the passiveirradiation to the scanning irradiation (namely, the irradiation device3B of the passive radiation type is replaced with an irradiation device4C of the scanning irradiation type).

In FIG. 13, the therapy system 400′ has the treatment room 7A equippedwith the passive irradiation device 3A and the treatment rooms 8A, 8Band 8C equipped with the scanning irradiation devices 4A, 4B and 4C,respectively. The treatment room 8C is a treatment room equipped withthe irradiation device 4C prepared by changing the irradiation method inthe treatment room 7B from passive irradiation to scanning irradiation.Detectors 33, 37 and 38 and scanning magnets 34, 35 all mounted in theirradiation device 4C are connected to a selector 71′ (indicated by ahatched area in FIG. 13) which is modified to have a newly addedswitching function. On the other hand, since the switching operation onthe side of the irradiation device 3A is no longer required, thedetectors 25, 29, 30 and 31 mounted in the irradiation device 3A areconnected to the beam detection processing/control unit 66 withoutinterposing the selector 70 therebetween.

When changing the irradiation method for the treatment room 7B frompassive irradiation to scanning irradiation like such a modification, inthe therapy system 500 of Comparative Example 2 described above withreference to FIG. 11, the beam detection processing/control unit 66Badapted for the passive irradiation must be entirely replaced with abeam detection processing/control unit adapted for the scanningirradiation. In contrast, as shown in FIG. 13, the therapy system 400 ofthis embodiment is easily adaptable for such a modification just byreconnecting the new irradiation device 4C of the scanning irradiationtype to the selector 71′ added with a correspondingly added switchingfunction. Another additional advantage is that the selector 70 for thepassive irradiation side can be dispensed with. It is therefore possibleto relatively easily change the irradiation method used in the treatmentroom and to improve the system flexibility.

Similarly, when adding a new treatment room, the therapy system 400 ofthis embodiment is adaptable for such an extension just by connecting anirradiation device installed in the new treatment room to the selector70 when the installed irradiation device is of the passive irradiationtype, and by connecting an irradiation device installed in the newtreatment room to the selector 71 when the installed irradiation deviceis of the scanning irradiation type, followed by adding a correspondingswitching function to the selector 70 or 71. It is therefore possible toeasily add a new treatment room and to improve the system extensibility.

In general, the scanning irradiation is required to handle a largernumber of input signals from the detectors and therefore to employ amore complicated beam detection processing/control unit than that in thepassive irradiation. Accordingly, the above-mentioned effects inimproving the system flexibility and extensibility become morenoticeable particularly when the irradiation method is changed frompassive irradiation to scanning irradiation, or when a new treatmentroom for the scanning irradiation is added.

Fourth Embodiment

A charged particle therapy system according to still another preferredembodiment of the present invention will be described below as a fourthembodiment. In contrast with the third embodiment in which the beamdetection processing/control unit is shared by the treatment roomsutilizing the same irradiation method, this fourth embodiment isconfigured such that the beam detection processing/control unit isfurther shared by the treatment rooms utilizing the differentirradiation methods.

FIG. 14 is an overall block diagram of a particle beam therapy system600 according to the fourth embodiment. As shown in FIG. 14, a beamdetection processing/control unit (monitoring unit, first control unit,and determining unit) 135 shared on the passive irradiation sideincludes control/processing sections 135 a, 135 b for monitoringrespectively the energy monitors 29 and the flatness monitors 30 amongthe detectors mounted in the passive irradiation devices 3A, 3B, while abeam detection processing/control unit (monitoring unit, first controlunit, determining unit, and scan stroke control unit) 136 shared on thescanning irradiation side includes control/processing sections 136 a,136 b for monitoring respectively the scanning magnets 34, 35 mounted inthe scanning irradiation devices 4A, 4B and the spot position monitors37 among the detectors mounted therein. Also, a beam detectionprocessing/control unit (monitoring unit, first control unit, anddetermining unit) 137 shared on both the passive irradiation and thescanning irradiation sides includes control/processing sections 137 a,137 b for monitoring respectively the profile monitors 25, 33 and thedose monitors 31, 38 among the detectors mounted in the passive andscanning irradiation devices 3A, 3B, 4A and 4B.

Although the constructions and functions of the selectors 70, 71 are thesame as those in the first to third embodiments described above, theconnection source side of the switching circuits 70 a, 70 d, 71 a and 71e is connected to a selector 140 instead of the beam detectionprocessing/control units. The selector 140 serves as a unit forswitching over a target, which is monitored by the beam detectionprocessing/control unit 137 to obtain the beam information, between thepassive irradiation side (i.e., the side of the passive irradiationdevices 3A, 3B) and the scanning irradiation side (i.e., the side of thescanning irradiation devices 4A, 4B). Then, the selector 140 has aswitching circuit 140 a for switching over the profile monitors 25, 33and a switching circuit 140 b for switching over the dose monitors 31,38. In other words, the switching-over between the profile monitors 25,33 and the switching-over between the dose monitors 31, 38 are eachperformed in two stages by the selector 140 and the selector 70 or 71.

The remaining configuration is the same as that in the above-describedthird embodiment, and hence a description thereof is omitted here.

Thus, with attention paid to the fact that some detectors, i.e., theprofile monitor and the dose monitor, are in common between theirradiation devices utilizing the different irradiation methods, i.e.,between the passive irradiation devices 3A, 3B and the scanningirradiation devices 4A, 4B, the therapy system of this embodiment isdesigned so as to share the beam detection processing/-control unit 137by the treatment rooms utilizing the different irradiation methods, inaddition to sharing each of the beam detection processing/control units135, 136 by the treatment rooms utilizing the same irradiation method asin the third embodiment. As a result, the system configuration can befurther simplified as compared with that in the third embodiment.

While the above embodiments have been described as providing, for eachof the treatment rooms, the display monitor and the operating/monitoringpanel which are used for monitoring the beam information, the displaymonitor and the operating/monitoring panel may also be used in common bya plurality of treatment rooms sharing the beam detectionprocessing/control unit. FIG. 15 shows a modification of the therapysystem 600, shown in FIG. 14, in which the control/monitoring panel ispartly shared by a plurality of treatment rooms. In FIG. 15, referencenumeral 141 denotes an operating/monitoring panel for the treatmentrooms utilizing the passive irradiation method, 142 denotes anoperating/monitoring panel for the treatment rooms utilizing thescanning irradiation method, and 143 denotes an operating/monitoringpanel shared by both the treatment rooms utilizing the passiveirradiation method and the scanning irradiation method. To display theitem of the beam information (e.g., an operating status) which cannot beshared by a plurality of treatment rooms, however, theoperating/monitoring panel is required to be provided in each of thetreatment control rooms 40A, 40B, 41A and 41B. Also, the console 49provided with the irradiation start button 46, the irradiation stopbutton 47, and the beam request button 48 is required to be provided ineach treatment control room from the viewpoint of avoiding a reductionin the operation efficiency of the therapy system.

1. A particle beam therapy system for irradiating a charged particlebeam to an affected part of the body for treatment, the therapy systemcomprising: a charged particle beam generator for generating the chargedparticle beam; a plurality of irradiation devices installed respectivelyin a plurality of treatment rooms and irradiating the charged particlebeam; a beam line for transporting the charged particle beam extractedfrom said charged particle beam generator to the irradiation device inselected one of said plurality of treatment rooms; a monitoring unit formonitoring a beam state of the charged particle beam in one of saidplurality of irradiation devices; a selector for switchably selectingone of said plurality of irradiation devices which is to be monitored bysaid monitoring unit; and a first control unit for controlling saidselector such that said selector establishes connection with theirradiation device in selected one of said plurality of treatment roomsto which the charged particle beam is transported through said beamline.
 2. The particle beam therapy system according to claim 1, furthercomprising a display unit for displaying the beam state of the chargedparticle beam in one of said plurality of irradiation devices, whereinsaid selector switchably selects one of said plurality of irradiationdevices to be displayed by said display unit.
 3. The particle beamtherapy system according to claim 1, wherein each of said plurality ofirradiation devices includes a detector for detecting beam informationof the charged particle beam, and said monitoring unit determineswhether the beam information of the charged particle beam detected bysaid detector is within an allowable range.
 4. The particle beam therapysystem according to claim 3, further comprising a second control unitfor controlling said charged particle beam generator to stop extractionof the charged particle beam when said monitoring unit determines thatthe beam information of the charged particle beam exceeds the allowablerange.
 5. The particle beam therapy system according to claim 4, furthercomprising a determining unit for determining whether said selector hasestablished connection with the irradiation device in the selected oneof said plurality of treatment rooms.
 6. The particle beam therapysystem according to claim 5, further comprising a third control unit forcontrolling said charged particle beam generator to stop extraction ofthe charged particle beam when said determining unit determines thatsaid selector has not established connection with the irradiation devicein the selected one of said plurality of treatment rooms.
 7. Theparticle beam therapy system according to claim 6, wherein saidplurality of irradiation devices are constructed as irradiation devicesutilizing the irradiation method.
 8. The particle beam therapy systemaccording to claim 7, wherein said plurality of irradiation devices areconstructed as irradiation devices operating in accordance with passiveirradiation.
 9. The particle beam therapy system according to claim 8,wherein each of said plurality of irradiation devices includes a profilemonitor for measuring the centroid and width of the charged particlebeam, an energy monitor for measuring energy of the charged particlebeam, a flatness monitor for measuring uniformity of the chargedparticle beam in a direction perpendicular to the direction of travel ofthe beam, and a dose monitor for measuring dose, and wherein saidmonitoring unit determines whether the beam information of the chargedparticle beam detected by said profile monitor, said energy monitor andsaid flatness monitor is within an allowable range, and whether the doseof the charged particle beam detected by said dose monitor has reached apreset value.
 10. The particle beam therapy system according to claim 7,wherein said plurality of irradiation devices are constructed asirradiation devices operating in accordance with scanning irradiation.11. The particle beam therapy system according to claim 10, wherein eachof said plurality of irradiation devices includes a profile monitor formeasuring the centroid and width of the charged particle beam, a spotposition monitor for measuring the centroid and width of the chargedparticle beam bent by a bending magnet, and a dose monitor for measuringdose, and wherein said monitoring unit determines whether the beaminformation of the charged particle beam detected by said profilemonitor and said spot position monitor is within an allowable range, andwhether the dose of the charged particle beam detected by said dosemonitor has reached a preset value.
 12. The particle beam therapy systemaccording to claim 6, wherein said plurality of irradiation devicesinclude irradiation devices utilizing at least two kinds of differentirradiation methods.
 13. The particle beam therapy system according toclaim 12, wherein said plurality of irradiation devices are made up ofirradiation devices operating in accordance with passive irradiation andscanning irradiation.
 14. The particle beam therapy system according toclaim 13, wherein each of said plurality of irradiation devices includesa profile monitor for measuring the centroid and width of the chargedparticle beam and a dose monitor for measuring dose, and wherein saidmonitoring unit determines whether the beam information of the chargedparticle beam detected by said profile monitor is within an allowablerange, and whether the dose of the charged particle beam detected bysaid dose monitor has reached a preset value.
 15. A particle beamtherapy system for irradiating a charged particle beam to an affectedpart of the body for treatment, the therapy system comprising: a chargedparticle beam generator for generating the charged particle beam; aplurality of irradiation devices installed respectively in a pluralityof treatment rooms and irradiating the charged particle beam; a beamline for transporting the charged particle beam extracted from saidcharged particle beam generator to the irradiation device in selectedone of said plurality of treatment rooms; a scan stroke control unit forcontrolling a scan stroke of the charged particle beam in one of saidplurality of irradiation devices; a selector for switchably selectingone of said plurality of irradiation devices to be controlled by saidscan stroke control unit; and a first control unit for controlling saidselector such that said selector establishes connection with theirradiation device in the selected one of said plurality of treatmentrooms to which the charged particle beam is transported through saidbeam line.
 16. The particle beam therapy system according to claim 15,wherein said scan stroke control unit controls a current value of saidscanning magnet for scanning the charged particle beam.
 17. A controlsystem for a particle beam therapy system having a plurality oftreatment rooms each provided with an irradiation device for irradiatinga charged particle beam, the control system comprising: a beam linecontrol unit for controlling a beam line such that the charged particlebeam is transported to the irradiation device in selected one of saidplurality of treatment rooms; a monitoring unit for monitoring a beamstate of the charged particle beam in one of said plurality ofirradiation devices; a selector for switchably selecting one of saidplurality of irradiation devices which is to be monitored by saidmonitoring unit; and a first control unit for controlling said selectorsuch that said selector establishes connection with the irradiationdevice in the selected one of said plurality of treatment rooms to whichthe charged particle beam is transported through said beam line.
 18. Thecontrol system for the particle beam therapy system according to claim17, wherein each of said plurality of irradiation devices includes adetector for detecting beam information of the charged particle beam,and said monitoring unit determines whether the beam information of thecharged particle beam detected by said detector is within an allowablerange.
 19. A control system for a particle beam therapy system having aplurality of treatment rooms each provided with an irradiation devicefor irradiating a charged particle beam in accordance with scanningirradiation, the control system comprising: a beam line control unit forcontrolling a beam line such that the charged particle beam istransported to the irradiation device in selected one of said pluralityof treatment rooms; a scan stroke control unit for controlling a scanstroke of the charged particle beam in one of said plurality ofirradiation devices; a selector for switchably selecting one of saidplurality of irradiation devices to be controlled by said scan strokecontrol unit; and a first control unit for controlling said selectorsuch that said selector establishes connection with the irradiationdevice in the selected one of said plurality of treatment rooms to whichthe charged particle beam is transported through said beam line.